I try clear install.
1. uninstall ver.8
"ESET Real-time File System Protection"(OFF) Remains on System Preference>Privacy & Security>Full Disk Access
2. "ESET Real-time File System Protection" delete on System Preference>Privacy & Security>Full Disk Access. use "-".
3. install ver.8. Onboarding.app ended without any problems.
From this, I imagine that macOS will not be able to recognize that "ESET Real-time File System Protection" has become new, macOS will not be able to grant permissions, and Onboarding.app will not progress.
The uninstaller also has a bug that cannot uninstall "ESET Real-time File System Protection".